Osg 1731305 Spiral Point Tap 7/16-20 Unf Tin Hss

Product Description

The OSG 1731305 is a spiral point plug tap designed for cutting right-hand internal threads in a 7/16-20 UNF configuration. Built from Vanadium High Speed Steel (HSS-E), it carries a Titanium Nitride (TiN) coating that extends tool life and reduces friction during threading operations. With 3 flutes and an H3 thread limit, this tap holds a 3B class of fit, making it appropriate for standard-tolerance threaded assemblies. The plug chamfer style eases entry into through-holes and is the most common choice for general production threading work. Machinists and tool-and-die professionals rely on this tap for consistent thread quality in ferrous and stainless steel applications.

This tap is suited for threading through-holes in hardened steel, low-carbon steel, medium-carbon steel, and stainless steel. It is used in general machining, toolroom work, and production environments where a reliable 7/16-20 UNF thread is required. The spiral point geometry pushes chips forward ahead of the tap, making it particularly effective in through-hole applications where chip evacuation is critical. The TiN coating improves performance when working with abrasive or harder materials.

Key Features

• 7/16-20 UNF thread form with H3 thread limit and 3B class of fit for standard-tolerance assemblies
• Vanadium High Speed Steel (HSS-E) construction for improved wear resistance over standard M2 HSS
• TiN coating reduces friction and extends tool life in steel and stainless applications
• 3-flute spiral point design pushes chips forward, optimized for through-hole threading
• Plug chamfer style for easy entry and general-purpose through-hole use
• Right-hand thread direction; no coolant-through feature

Compatibility

Compatible material applications include hardened steel, low-carbon steel, medium-carbon steel, and stainless steel as stated in the product specifications. Suitable for use in any standard tapping chuck or CNC tapping cycle that accepts a straight-shank tap with a 0.323-inch shank diameter.

Installation Notes

This tap is installed by a machinist or toolroom technician using a standard tap wrench, tapping head, or CNC machine tool spindle. Always ensure the workpiece is securely fixtured and the correct tap drill size for 7/16-20 UNF has been used before threading. Use an appropriate cutting fluid or tapping compound for the workpiece material to protect both the tap and the thread finish. Inspect the tap for wear or chipping before each use and never force a tap that has stopped feeding freely.